A day after a Murrysville, Pennsylvania, teen allegedly rampaged through his high school's hallways, stabbing wildly with two kitchen knives, the first hints of a possible motive began to emerge.

The attorney for 16-year-old Alex Hribal raised the specter that his client may have been bullied, telling CNN affiliate WTAE in Pittsburgh on Thursday that it looks like some kind of "bullying event" may have played a role.

"I think a lot of things have happened. I don't want to comment specifically, but I think there are some things that occurred that led to where we are today," Patrick Thomassey said.

But an FBI official, familiar with the investigation, discounted bullying as a motive.

"He was disaffected but not bullied," the official said on condition of anonymity.

Hribal, a sophomore, was charged as an adult and faces four counts of attempted homicide and 21 counts of aggravated assault in connection with Wednesday's attack at Franklin Regional Senior High School that left 20 teens and one adult wounded.

Some classmates at the school describe Hribal as having few friends and being quiet but also as a "really nice kid," a description that contradicts the image of a knife-wielding teen offered by authorities.

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Stabbings at Pennsylvania high school 12 photos

Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – Parents and students embrace near Franklin Regional High School, where authorities say at least 20 people were injured in a stabbing spree Wednesday, April 9, in Murrysville, Pennsylvania.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – Accused attacker Alex Hribal, 16, is escorted from a district magistrate after he was arraigned as an adult on April 9. He faces four counts of attempted homicide, 21 counts of aggravated assault and one count of possession of a weapon on school grounds, according to a criminal complaint made public.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – A police officer blocks the entrance to the school on April 9.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – Students leave the school's campus on April 9.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – A police officer stands by the scene outside the high school on April 9.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – A woman walks onto the campus of the Franklin Regional School District on April 9.

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Stabbings at Pennsylvania high school – Students walk away from the campus on April 9.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – Emergency responders gather in the parking lot of Franklin Regional High School on April 9.

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Stabbings at Pennsylvania high school12 photos

Stabbings at Pennsylvania high school – Jenna Mickel, a sophomore at Franklin Regional High School, stands with her father, Richard, as she talks to reporters outside the school on April 9.

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Stabbings at Pennsylvania high school – Emergency responders gather in the high school's parking lot.

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Stabbings at Pennsylvania high school – A pair of women leave the school's campus on April 9.

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Stabbings at Pennsylvania high school – A Salvation Army disaster services vehicle drives past a school bus and onto the campus on April 9.

"I came out here purposely to raise my children in a school district that we felt was safe as well as academically sound."

The mother of one of the teens wounded in the attack said everyone must ask themselves what alienated the suspect so much that he allegedly stabbed and slashed nearly two dozen people.

"...We need to look and say, how are our children coping with social skills these days? How are they with other children? How are they being tested in the world for negative or positive ways?" said Amanda Hurt.

Her son, Brett, was in the school hallway when he saw a "kid" run by and hit him in the back.

A friend who was with him started screaming.

"I didn't really know what was going on at the time," Hurt told reporters. "It was all kind of a blur."

As the attacker continued to charge down the crowded hallway, Hurt began to wonder if he was going to survive or die.

Speaking from the hospital, Hurt said he suffered a stab wound in the back and a bruised lung. He expected to be released as early as Thursday.

He reflected on whether Hribal would have chosen the path he allegedly did if he had had more friends or a better support group.

"I feel he has some issues he has to work out," Hurt said.

Another student at the school who witnessed the attack said the attacker didn't utter a word.

"He was very quiet. He just was kind of doing it," Mia Meixner said. "And he had this, like, look on his face that he was just crazy and he was just running around, just stabbing whoever was in his way."

"This is not a dysfunctional family," Thomassey, told CNN on Thursday. "They're like the Brady Bunch. These parents are active with their two sons, and we're trying to figure out what happened."

The young man also did not seem to embody the cliche of digitally connected youth.

According to Dan Stevens, the county deputy emergency management coordinator, Hribal had a very minor Facebook presence and didn't have much experience on Twitter.

Thomassey said he would file a motion to move the case to juvenile court.

Westmoreland County District Attorney John Peck has argued against bail, saying that there could be no conditions that would protect the community and that Hribal made "statements when subdued by officials that he wanted to die."

Hribal is being held without bail at the Westmoreland County juvenile detention center. He was treated for injuries to his hands, police said.

The students who were hurt range in age from 14 to 17, emergency coordinator Stevens said. The injuries were stabbing-related, such as lacerations or punctures.